Submission #830858

#	Time	Username	Problem	Language	Result	Execution time	Memory
830858		howard0027	Knapsack (NOI18_knapsack)	C11	100 / 100	671 ms	292 KiB

knapsack

//knapsack.c
#include<stdio.h>

int main()
{
	int s, n;
	int dp[2001] = {0};
	scanf("%d%d", &s, &n);
	//s = 2000, n = 100000;
	
	for (int i = 0; i < n; ++i)
	{
		int v, w, k;
		scanf("%d%d%d", &v, &w, &k);
		//v = 1000000, w = 1, k = 1000000000;
		for (int r = 0; r < w; ++r)
		{
			int dq[2001][2];
			int head = 0, tail = 0;
			for (int q = 0, j = r; j <= s; ++q, j += w)
			{
				int mn = q;
				
				if (mn > k)
				{
					mn = k; // min(q, k)
				}
				
				while (tail - head > 0 && dq[head][1] < q - mn)
				{
					++head;
				}
				
				while (tail - head > 0 && dq[tail - 1][0] <= dp[j] - q * v)
				{
					--tail;
				}
				
				dq[tail][0] = dp[j] - q * v;
				dq[tail][1] = q;
				++tail;
				
				dp[j] = dq[head][0] + q * v;
			}
		}
	}
	
	printf("%d\n", dp[s]);
	
	return 0;
}

Compilation message (stderr)

knapsack.c: In function 'main':
knapsack.c:8:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
    8 |  scanf("%d%d", &s, &n);
      |  ^~~~~~~~~~~~~~~~~~~~~
knapsack.c:14:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   14 |   scanf("%d%d%d", &v, &w, &k);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 17 / 17
• Subtask 3: 20 / 20
• Subtask 4: 24 / 24
• Subtask 5: 27 / 27